This communication presents a novel compact and wideband circularly polarized (CP) slot antenna fed by microstrip feedline. The proposed antenna consists of a corner-truncated square-ring slot patch and a novel bent strip. The CP radiation is formed by using the bent strip to excite CP resonance modes. By intruding several open stubs to the corners of the square-ring slot patch, the impedance matching and axial ratio (AR) bandwidth are improved. The measured results show that the proposed antenna has the advantage of wideband characteristics in terms of an impedance bandwidth of 90.59% (3.2-8.5 GHz) and 3-dB axial ratio bandwidth of 84.2% (3.3-8.1 GHz). The principle as well as simulated and measured results of the proposed antenna is revealed.
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